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1.
Int J Pharm ; 607: 120959, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34333025

RESUMO

Isosorbide (ISO) is an effective hyperosmotic agent that can be administrated orally and is used as a therapeutic agent for brain pressure drop, glaucoma, and Meniere's disease. However, the critical relative humidity (CRH) of ISO is about 48% RH at 25 °C, and it deliquesces in humid environments. In this study, we attempted to reduce the deliquescence of ISO using cocrystallization and analyze the water adsorption mechanism from the crystal structure. Four new ISO cocrystals with piperazine (PZ), hydrochlorothiazide (HCT), 3,5-dihydroxybenzoic acid (35DHBA), or gallic acid (GA) were identified. The dynamic vapor sorption analyses demonstrated that all the cocrystals showed higher CRHs than the ISO crystal. Although water adsorption below the CRH was observed for all cocrystals, the water molecules adsorbed in the ISO-PZ and ISO-GA cocrystals were lower than those in the ISO crystal. Investigation of the crystal structures suggested that the amount of water adsorbed might be related to the degree of exposure of the ISO hydroxyl groups on the crystal surface. Given the CRH, water adsorption below the CRH, thermal stability, apparent dissolution rate, and toxicity level of the coformer, the ISO-GA cocrystal is the most suitable for preparing a solid formulation of ISO.


Assuntos
Isossorbida , Água , Cristalização , Solubilidade , Molhabilidade , Difração de Raios X
2.
Biomacromolecules ; 22(2): 640-648, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33307669

RESUMO

We have prepared a series of 12 d-isosorbide-2-alkanoate-5-methacrylate monomers as single regioisomers with different pendant linear C2-C20 alkanoyl chains using biocatalytic and chemical acylations. By conventional radical polymerization, these monomers provided high-molecular-weight biobased poly(alkanoyl isosorbide methacrylate)s (PAIMAs). Samples with C2-C12 alkanoyl chains were amorphous with glass transition temperatures from 107 to 54 °C, while C14-C20 chains provided semicrystalline materials with melting points up to 59 °C. Moreover, PAIMAs with C13-C20 chains formed liquid crystalline mesophases with transition temperatures up to 93 °C. The mesophases were studied using polarized optical microscopy, and rheology showed stepwise changes of the viscosity at the transition temperature. Unexpectedly, a PAIMA prepared from a regioisomeric monomer (C18) showed semicrystallinity but not liquid crystallinity. Consequently, the properties of the PAIMAs were readily tunable by controlling the phase structure and transitions through the alkanoyl chain length and the regiochemistry to form fully amorphous, semicrystalline, or semi/liquid crystalline materials.


Assuntos
Isossorbida , Cristais Líquidos , Metacrilatos , Polimerização , Viscosidade
3.
Molecules ; 25(23)2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-33291362

RESUMO

Lactic acid is one of the key biobased chemical building blocks, given its readily availability from sugars through fermentation and facile conversion into a range of important chemical intermediates and polymers. Herein, well-defined rubbery polymers derived from butyl lactate solvent were successfully prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization of the corresponding monomeric acrylic derivative. Good control over molecular weight and molecular weight distribution was achieved in bulk using either monofunctional or bifunctional trithiocarbonate-type chain transfer agents. Subsequently, poly(butyl lactate acrylate), with a relative low Tg (-20 °C), good thermal stability (5% wt. loss at 340 °C) and low toxicity was evaluated as a sustainable middle block in all-acrylic ABA copolymers using isosorbide and vanillin-derived glassy polyacrylates as representative end blocks. Thermal, morphological and mechanical properties of copolymers containing hard segment contents of <20 wt% were evaluated to demonstrate the suitability of rubbery poly(alkyl lactate) building blocks for developing functional sustainable materials. Noteworthy, 180° peel adhesion measurements showed that the synthesized biosourced all-acrylic ABA copolymers possess competitive performance when compared with commercial pressure-sensitive tapes.


Assuntos
Acrilatos/química , Ácido Láctico/química , Polímeros/química , Benzaldeídos/química , Isossorbida/química , Lactatos/química , Polimerização , Solventes/química
4.
Int J Biol Macromol ; 164: 2028-2037, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32791270

RESUMO

Green biocomposites based on corn starch plasticized with isosorbide and glycerol and filled with microcrystalline cellulose (MCC) were processed. The structural interactions, dynamomechanical properties, water absorption, and soil biodegradability were investigated by different techniques considering the effect of the type and amount of plasticizer and the MCC addition. The changes along the time of the structural interactions and the dynamomechanical properties of these materials and the influence of the retrogradation phenomenon were also studied. The use of isosorbide as plasticizer instead of glycerol improved the stiffness, the water absorption and the biodegradation rate of thermoplastic starch (TPS). Moreover, no evidence of retrogradation for isosorbide was observed. An isosorbide content of 35% and the addition of MCC filler enhanced in a greater extent these properties with a complete biodegradability in 7 month. These green biocomposites can be an alternative for food packaging applications.


Assuntos
Celulose/química , Isossorbida/química , Plastificantes/química , Amido/química , Plásticos Biodegradáveis/química , Biodegradação Ambiental , Glicerol/química , Solo/química , Água/química
5.
Biomacromolecules ; 21(11): 4522-4531, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-32441934

RESUMO

Growing environmental concerns are enforcing sustainable recycling processes for glass substrates, especially bottles, where a fast cleaning and minimization of the use of solvents is desired. In this process, labels and adhesives are mostly removed by the addition of harsh reagents, alkaline solutions, or high temperature, increasing economic costs and harming the environment. Herein, high performance and biobased waterborne pressure-sensitive adhesives with fast removability in water have been developed using small percentages of isosorbide (derived from glucose)-based methacrylate monomers. Formulations containing 2-octyl acrylate and isobornyl methacrylate and small amounts (1 wt %) of these monomers not only yield stronger adhesive fibrils, but also promote a removability in water 6× faster than that of nonisosorbide-based counterparts. This waterborne isosorbide containing PSAs represents an alternative to current PSA formulations toward more sustainable glass recycling and reusing processes.


Assuntos
Adesivos , Isossorbida , Vidro , Metacrilatos , Água
6.
J Comp Eff Res ; 9(6): 405-412, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32301331

RESUMO

Aim: The cost-effectiveness of isosorbide-5-mononitrate (5-ISMN) and isosorbide dinitrate (ISDN) in real-world use in patients with coronary heart disease (CHD; either angina pectoris or myocardial infarction) was retrospectively compared. Method: In this retrospective real-world evaluation, patients with established CHD satisfying the following criteria were selected from information system of two tertiary hospitals in China: with pharmacy claiming for at least one injection of 5-ISMN or ISDN between July 2008 and May 2017; and, CHD patients. By using propensity score matching (PSM), we compared clinical aspects of efficacy, safety, length of hospital stay and cost during hospitalization between 5-ISMN and ISDN group. All data were processed by R statistical package v.2.13.1 (R Foundation for Statistical Computing, Vienna, Austria). Result: Of 5609 patients selected, 4047 received 5-ISMN and 1562 received ISDN. After PSM, we acquired 1555 pairs based on balancing of age, sex, insurance and comorbidities on admission. The frequency (4.2 ± 6.6-times vs 6.5 ± 9.5-times; p < 0.05) and total dosage (47.5 ± 153.4 vs 136.4 ± 261.0 mg; p < 0.05) of sublingual nitroglycerin use decreased and hypotension incidence lowered (8.0 vs 13.0%; p < 0.05) in 5-ISMN group compared with ISDN group. Hospital stay (16.0 ± 11.3 days vs 17.7 ± 13.2; p < 0.05) and hospitalization expenditure ([the ratio of cost in the study to the average hospitalization cost in the city] [odds ratio: 2.5 vs 2.6; p < 0.05]) were reduced in 5-ISMN group as with that of ISDN group. Moreover, the main component of hospitalization cost was medical consumables and medications in both the groups. Conclusion: In the present retrospective real-world evaluation, by using PSM analysis, we found that newer injection agent of 5-ISMN was associated with fewer use of sublingual nitroglycerin, less hypotension incidence, shorter length of hospital stay and less hospitalization expenditure related to its comparator ISDN in patients with established CHD. Further evaluation and clinical experience are need in different circumference for the usage of ISDN.


Assuntos
Doença das Coronárias/tratamento farmacológico , Custos de Cuidados de Saúde/estatística & dados numéricos , Dinitrato de Isossorbida/análogos & derivados , Dinitrato de Isossorbida/uso terapêutico , Isossorbida/uso terapêutico , Administração Sublingual , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Doença das Coronárias/economia , Análise Custo-Benefício , Feminino , Humanos , Hipotensão/epidemiologia , Incidência , Isossorbida/economia , Dinitrato de Isossorbida/economia , Tempo de Internação/economia , Masculino , Pessoa de Meia-Idade , Doadores de Óxido Nítrico/economia , Doadores de Óxido Nítrico/uso terapêutico , Nitroglicerina/administração & dosagem , Ensaios Clínicos Pragmáticos como Assunto , Pontuação de Propensão , Estudos Retrospectivos , Vasodilatadores/economia , Vasodilatadores/uso terapêutico
7.
ACS Biomater Sci Eng ; 6(5): 2578-2587, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33463273

RESUMO

Although emergence of bone tissue engineering techniques has revolutionized the field of maxillofacial reconstruction, the successful translation of such products, especially concerning larger sized defects, still remains a significant challenge. Light-curable methacrylate-based polymers have ideal properties for bone repair. These materials are also suitable for 3D printing which can be applicable for restoration of both function and aesthetics. The main objective of this research was to synthesize a mechanically stable and biologically functional polymer for reconstruction of complex craniofacial defects. The experimental work initially involved synthesis of (((3R,3aR,6S,6aR)-hexahydrofuro[3,2-b]furan-3,6-diyl)bis(oxy))bis(ethane-2,1-diyl)bis((4-methyl-3-oxopent-4-en-1-yl)carbamate), CSMA-1, and ((((((((((((3R,3aR,6S,6aR)-hexahydrofuro[3,2-b]furan-3,6-diyl)bis(oxy))bis(ethane-2,1 diyl))bis(oxy))bis(carbonyl))bis(azanediyl))bis(methylene))bis(3,3,5-trimethylcyclohexane-5,1-diyl))bis(azanediyl))bis(carbonyl))bis(oxy))bis(ethane-2,1-diyl)bis(2-methylacrylate), CSMA-2; nuclear magnetic resonance analysis confirmed formation of the monomers, and composite samples were fabricated respectively by exposing 11 mm diameter discs to blue light. Modulus of elasticity was determined using a biaxial flexural test and the values were found to be between 1 and 3 GPa in CSMA-1, CSMA-2, and their composites. In vitro cell culture, using human bone marrow-derived mesenchymal stem cells, confirmed nontoxicity of the samples and finally 3D printing allowed direct photo-polymerization and setting of the bio ink into a 3D construct.


Assuntos
Isossorbida , Polímeros , Elasticidade , Humanos , Metacrilatos , Impressão Tridimensional
8.
Int J Pharm ; 569: 118549, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31394188

RESUMO

Trial-and-error approach to formulation development is long and costly. With growing time and cost pressures in the pharmaceutical industry, the need for computer-based formulation design is greater than ever. In this project, emulgels were designed and optimized using Formulating for Efficacy™ (FFE) for the topical delivery of ibuprofen. FFE helped select penetration enhancers, design and optimize emulgels and simulate skin penetration studies. pH, viscosity, spreadability, droplet size and stability of emulgels were evaluated. Franz cell studies were performed to test in vitro drug release on regenerated cellulose membrane, drug permeation in vitro on Strat-M® membrane and ex vivo on porcine ear skin, a marketed ibuprofen gel served as control. Emulgels had skin compatible pH, viscosity and spreadability comparable to a marketed emulgel, were opaque and stable at 25 °C for 6 months. Oleyl alcohol (OA), combined with either dimethyl isosorbide (DMI) or diethylene glycol monoethyl ether (DGME) provided the highest permeation in 24 h in vitro, which was significantly higher than the marketed product (p < 0.01). OA + DGME significantly outperformed OA ex vivo (p < 0.05). The computer predictions, in vitro and ex vivo penetration results correlated well. FFE was a fast, valuable and reliable tool for aiding in topical product design for ibuprofen.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Absorção Cutânea , Animais , Química Farmacêutica , Simulação por Computador , Composição de Medicamentos , Etilenoglicóis/administração & dosagem , Etilenoglicóis/química , Álcoois Graxos/administração & dosagem , Álcoois Graxos/química , Técnicas In Vitro , Isossorbida/administração & dosagem , Isossorbida/análogos & derivados , Isossorbida/química , Pele/metabolismo , Solubilidade , Suínos
9.
J Mech Behav Biomed Mater ; 100: 103371, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31362097

RESUMO

The objective of this study was to synthesize two bio-based monomers from isosorbide, the bis(allylcarbonate) isosorbide (IBAC) and the bis(methacrylate) isosorbide (IBM), and to evaluate its effect as Bis-GMA diluents in the formulation of photopolymerizable dental composite resins. The chemical structure of both bio-based monomers was determinate by means H1 NMR, C13 NMR and FTIR spectroscopies. Experimental composites comprising Bis-GMA/IBAC or Bis-GMA/IBM were formulated using 65 %wt of silanized inorganic filler. Experimental materials were compared with a control composite formulated with Bis-GMA/TEGDMA. Double bond conversion, polymerization kinetics, volumetric shrinkage, water sorption, solubility, and flexural properties were investigated. The data were analyzed by one-way ANOVA and Tukey test (α = 0.05). Flexural strength of the experimental materials was similar to the control (p = 0.733). Bis-GMA/IBM achieved the highest values of elastic modulus (p = 0.135). Bis-GMA/IBAC composite achieved the highest values of degree of conversion, while the values of Bis-GMA/IBM composite were similar to the control (p > 0.05). There were no differences in the polymerization shrinkage of the composites, however, the polymerization stress of the experimental materials was lower (p < 0.05). Finally, the cell viability test showed that the experimental resins formulated with the bio-based monomers were not cytotoxic. Due to its characteristics, IBAC and IBM monomers are potentially useful for the formulation of composite materials with applications in dentistry.


Assuntos
Resinas Acrílicas/química , Bis-Fenol A-Glicidil Metacrilato/química , Resinas Compostas/química , Isossorbida/farmacologia , Poliuretanos/química , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Sobrevivência Celular , Odontologia , Módulo de Elasticidade , Elasticidade , Fibroblastos/efeitos dos fármacos , Cinética , Espectroscopia de Ressonância Magnética , Teste de Materiais , Camundongos , Peso Molecular , Fotoquímica , Polimerização , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Temperatura , Viscosidade
10.
Molecules ; 24(13)2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288408

RESUMO

Demand for the development of novel polymers derived from biomass that can replace petroleum resources has been increasing. In this study, biomass-derived isosorbide was used as a monomer in the polymerization of poly(arylene ether ketone)s, and its synthetic characteristics were investigated. As a phase-transfer catalyst, crown ether has increased the weight-average molecular weight of polymers over 100 kg/mol by improving the reaction efficiency of isosorbide and minimizing the effect of moisture. By controlling the experimental parameters such as halogen monomer, polymerization solvent, time, and temperature, the optimal conditions were found to be fluorine-type monomer, dimethyl sulfoxide, 24 h, and 155 °C, respectively. Biomass contents from isosorbide-based polymers were determined by nuclear magnetic resonance and accelerator mass spectroscopy. The synthesized polymer resulted in a high molecular weight that enabled the preparation of transparent polymer films by the solution casting method despite its weak thermal degradation stability compared to aromatic polysulfone. The melt injection molding process was enabled by the addition of plasticizer. The tensile properties were comparable or superior to those of commercial petrochemical specimens of similar molecular weight. Interestingly, the prepared specimens exhibited a significantly lower coefficient of thermal expansion at high temperatures over 150 °C compared to polysulfone.


Assuntos
Biomassa , Isossorbida/análogos & derivados , Isossorbida/química , Cetonas/química , Plásticos/química , Catálise , Éteres/química , Temperatura Alta , Peso Molecular , Sulfonas/química
11.
Molecules ; 24(9)2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-31027338

RESUMO

The substitution of toxic precursors such as bisphenol A by renewable and safer molecules has become a major challenge. To overcome this challenge, the 12 principles of green chemistry should be taken into account in the development of future sustainable chemicals and processes. In this context, this paper reports the highly efficient synthesis of oligo-isosorbide glycidyl ethers from bio-based starting materials by a rapid one-pot heterogeneous ultrasound-assisted synthesis. It was demonstrated that the use of high-power ultrasound in solvent-free conditions with sodium hydroxide microbeads led for the first time to a fully epoxidated prepolymer with excellent epoxy equivalent weight (EEW). The structure of the epoxy precursor was characterized by FT-IR, NMR spectroscopy and high-resolution mass spectrometry (HRMS). The efficiency of the ultrasound-assisted synthesis was attributed to the physical effects caused by micro-jets on the surface of the solid sodium hydroxide microspheres following the asymmetrical collapse of cavitation bubbles.


Assuntos
Técnicas de Química Sintética , Compostos de Epóxi/química , Isossorbida/química , Ondas Ultrassônicas , Compostos de Epóxi/síntese química , Química Verde , Isossorbida/síntese química , Estrutura Molecular , Análise Espectral
12.
Molecules ; 24(7)2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-30959785

RESUMO

Isosorbide (ISB), a nontoxic bio-based bicyclic diol composed from two fuzed furans, was incorporated into the preparation of flexible polyurethane foams (FPUFs) for use as a cell opener and to impart antioxidant properties to the resulting foam. A novel method for cell opening was designed based on the anticipated reversibility of the urethane linkages formed by ISB with isocyanate. FPUFs containing various amounts of ISB (up to 5 wt%) were successfully prepared without any noticeable deterioration in the appearance and physical properties of the resulting foams. The air permeability of these resulting FPUFs was increased and this could be further improved by thermal treatment at 160 °C. The urethane units based on ISB enabled cell window opening, as anticipated, through the reversible urethane linkage. The ISB-containing FPUFs also demonstrated better antioxidant activity by impeding discoloration. Thus, ISB, a nontoxic, bio-based diol, can be a valuable raw material (or additive) for eco-friendly FPUFs without seriously compromising the physical properties of these FPUFs.


Assuntos
Antioxidantes/química , Isossorbida/química , Permeabilidade/efeitos dos fármacos , Poliuretanos/química , Antioxidantes/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Isocianatos/química , Isocianatos/farmacologia , Isossorbida/farmacologia , Poliuretanos/farmacologia , Uretana/química
13.
Molecules ; 24(6)2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-30889870

RESUMO

Polyurethane (PU) is a versatile polymer used in a wide range of applications. Recently, imparting PU with self-healing properties has attracted much interest to improve the product durability. The self-healing mechanism conceivably occurs through the existence of dynamic reversible bonds over a specific temperature range. The present study investigates the self-healing properties of 1,4:3,6-dianhydrohexitol-based PUs prepared from a prepolymer of poly(tetra-methylene ether glycol) and 4,4'-methylenebis(phenyl isocyanate) with different chain extenders (isosorbide or isomannide). PU with the conventional chain extender 1,4-butanediol was prepared for comparison. The urethane bonds in 1,4:3,6-dianhydrohexitol-based PUs were thermally reversible (as confirmed by the generation of isocyanate peaks observed by Fourier transform infrared spectroscopy) at mildly elevated temperatures and the PUs showed good mechanical properties. Especially the isosorbide-based polyurethane showed potential self-healing ability under mild heat treatment, as observed in reprocessing tests. It is inferred that isosorbide, bio-based bicyclic diol, can be employed as an efficient chain extender of polyurethane prepolymers to improve self-healing properties of polyurethane elastomers via reversible features of the urethane bonds.


Assuntos
Elastômeros/síntese química , Isossorbida/síntese química , Poliuretanos/síntese química , Temperatura , Varredura Diferencial de Calorimetria , Módulo de Elasticidade , Elastômeros/química , Isossorbida/química , Microscopia de Força Atômica , Peso Molecular , Poliuretanos/química , Espalhamento a Baixo Ângulo , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Termogravimetria , Difração de Raios X
14.
Clin Cardiol ; 42(1): 21-25, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30054906

RESUMO

BACKGROUND: Adequate hydration remains the mainstay of contrast-induced nephropathy prevention, and nitrates could reduce cardiac preload. HYPOTHESIS: This study aimed to explore the adequate hydration with nitrates for patients with chronic kidney disease (CKD) and congestive heart failure (CHF) to reduce the risk of contrast-induced nephropathy (CIN) and at the same time avoid the acute heart failure. METHODS: Three hundred and ninty-four consecutive patients with CKD and CHF undergoing coronary procedures were randomized to either adequate hydration with nitrates (n = 196) or to routine hydration (control group; n = 198). The adequate hydration group received continuous intravenous infusion of isosorbide dinitrate combined with intravenous infusion of isotonic saline at a rate of 1.5 mL/kg/h during perioperative period. The definition of CIN was a 25% or 0.5 mg/dL rise in serum creatinine over baseline. This trial is registered with www.clinicaltrials.gov, number NCT02718521. RESULTS: Baseline characteristics were well-matched between the two groups. CIN occurred less frequently in adequate hydration group than the control group (12.8% vs 21.2%; P = 0.018). The incidence of acute heart failure did not differ between the two groups (8 [4.08%] vs 6[3.03%]; P = 0.599). Cumulative major adverse events (death, myocardial infarction, stoke, hospitalization for acute heart failure) during the 90-day follow-up were lower in the adequate hydration with nitrates group (P = 0.002). CONCLUSIONS: Adequate hydration with nitrates can safely and effectively reduce the risk of CIN in patients with CKD and CHF.


Assuntos
Injúria Renal Aguda/prevenção & controle , Aspirina/análogos & derivados , Meios de Contraste/efeitos adversos , Hidratação/métodos , Insuficiência Cardíaca/complicações , Isossorbida/análogos & derivados , Insuficiência Renal Crônica/complicações , Injúria Renal Aguda/induzido quimicamente , Idoso , Aspirina/administração & dosagem , China/epidemiologia , Angiografia Coronária , Método Duplo-Cego , Feminino , Seguimentos , Insuficiência Cardíaca/diagnóstico , Humanos , Incidência , Infusões Intravenosas , Isossorbida/administração & dosagem , Masculino , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
15.
PLoS Negl Trop Dis ; 12(9): e0006836, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30265663

RESUMO

BACKGROUND: Chagas disease is a neglected tropical disease. About 6 to 8 million people are chronically infected and 10% to 15% develop irreversible gastrointestinal disorders, including megaesophagus. Treatment focuses on improving symptoms, and isosorbide and nifedipine may be used for this purpose. METHODOLOGY: We conducted a systematic review to evaluate the effectiveness of pharmacological treatment for Chagas' megaesophagus. We searched MEDLINE, Embase and LILACS databases up to January 2018. We included both observational studies and RCTs evaluating the effects of isosorbide or nifedipine in adult patients with Chagas' megaesophagus. Two reviewers screened titles and abstracts, selected eligible studies and extracted data. We assessed the risk of bias using NIH 'Quality Assessment Tool for Before-After (Pre-Post) Studies with No Control Group' and RoB 2.0 tool. Overall quality of evidence was assessed using GRADE. PRINCIPAL FINDINGS: We included eight studies (four crossover RCTs, four before-after studies). Three studies evaluated the effect of isosorbide on lower esophageal sphincter pressure (LESP), showing a significant reduction (mean difference -10.52mmHg, 95%CI -13.57 to-7.47, very low quality of evidence). Three studies reported the effect of isosorbide on esophageal emptying, showing a decrease in esophageal retention rates (mean difference -22.16%, 95%CI -29.94 to -14.38, low quality of evidence). In one study, patients on isosorbide reported improvement in the frequency and severity of dysphagia (moderate quality of evidence). Studies evaluating nifedipine observed a decrease in LESP but no effect on esophageal emptying (very low and low quality of evidence, respectively). Isosorbide had a higher incidence of headache as a side effect than nifedipine. CONCLUSIONS: Although limited, available evidence shows that both isosorbide and nifedipine are effective in reducing esophageal symptoms. Isosorbide appears to be more effective, and its use is supported by a larger number of studies; nifedipine, however, appears to have a better tolerability profile. TRIAL REGISTRATION: PROSPERO CRD42017055143. ClinicalTrials.gov CRD42017055143.


Assuntos
Doença de Chagas/complicações , Acalasia Esofágica/tratamento farmacológico , Isossorbida/administração & dosagem , Nifedipino/administração & dosagem , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
16.
J Oleo Sci ; 67(8): 925-931, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30068827

RESUMO

Highly viscous hydrophobic isosorbide biobased polyester O/W emulsions are prepared through catastrophic phase inversion. The process is followed in situ with two different methods: torque and light backscattering (LBS). Considering high viscosity of the system, only discontinuous conductivity monitoring is performed for comparison. Torque and LBS allow to highlight the emulsion inversion point (EIP) with relatively close water weight fraction values (fw≈0.20). The torque and LBS signals are rather noisy before inversion (evolution of different structures) and more smooth after phase inversion (continuous aqueous phase). Torque gives a more macroscopic information, representative of the global state of the dispersion. Consistent conductivity and torque measurements suggest indeed an inversion pathway through multiple o/W/O emulsions leading to multiple complex structures before getting continuous aqueous final emulsion. This hypothesis is confirmed with continuous LBS monitoring and microscopic observations. LBS signal seems more complete because it combines the information of conductivity and torque and allows to clearly follow in situ the inversion from the beginning to the end of the process.


Assuntos
Difusão Dinâmica da Luz/métodos , Isossorbida/química , Poliésteres/química , Torque , Emulsões , Interações Hidrofóbicas e Hidrofílicas , Óleos/química , Transição de Fase , Viscosidade , Água/química
17.
Anal Chem ; 90(16): 10031-10038, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30024732

RESUMO

The combination of microspotting of analytical and internal standards, matrix sublimation, and recently developed software for quantitative mass spectrometry imaging has been used to develop a high-resolution method for the determination of terbinafine hydrochloride in the epidermal region of a full thickness living skin equivalent model. A quantitative assessment of the effect of the addition of the penetration enhancer (dimethyl isosorbide (DMI)) to the delivery vehicle has also been performed, and data have been compared to those obtained from LC-MS/MS measurements of homogenates of isolated epidermal tissue. At 10% DMI, the levels of signal detected for the drug in the epidermis were 0.20 ± 0.072 mg/g tissue for QMSI and 0.28 ± 0.040 mg/g tissue for LC-MS/MS at 50% DMI 0.69 ± 0.23 mg/g tissue for QMSI and 0.66 ± 0.057 mg/g tissue for LC-MS/MS. Comparison of means and standard deviations indicates no significant difference between the values obtained by the two methods.


Assuntos
Antifúngicos/análise , Absorção Cutânea , Pele/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Terbinafina/análise , Antifúngicos/metabolismo , Isossorbida/análogos & derivados , Isossorbida/metabolismo , Terbinafina/metabolismo
18.
Biomacromolecules ; 19(7): 3077-3085, 2018 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-29897737

RESUMO

Biobased unsaturated polyester thermosets as potential replacements for petroleum-based thermosets were designed. The target of incorporating rigid units, to yield thermosets with high thermal and mechanical performance, both in the biobased unsaturated polyester (UP) and reactive diluent (RD) while retaining miscibility was successfully achieved. The biobased unsaturated polyester thermosets were prepared by varying the content of isosorbide, 1,4-butanediol, maleic anhydride, and succinic anhydride in combination with the reactive diluent isosorbide-methacrylate (IM). Isosorbide was chosen as the main component in both the UP and the RD to enhance the rigidity of the formed thermosets, to overcome solubility issues commonly associated with biobased UPs and RDs and volatility and toxicity associated with styrene as RD. All UPs had good solubility in the RD and the viscosity of the mixtures was primarily tuned by the feed ratio of isosorbide but also by the amount of maleic anhydride. The flexural modulus and storage modulus were tailorable by altering the monomer composition The fabricated thermosets had superior thermal and mechanical properties compared to most biobased UP thermosets with thermal stability up to about 250 °C and a storage modulus at 25 °C varying between 0.5 and 3.0 GPa. These values are close to commercial petroleum-based UP thermosets. The designed tailorable biobased thermosets are, thus, promising candidates to replace their petroleum analogs.


Assuntos
Fontes Geradoras de Energia , Isossorbida/química , Poliésteres/síntese química , Butileno Glicóis/química , Anidridos Maleicos/química , Metacrilatos/química , Poliésteres/toxicidade , Solubilidade , Anidridos Succínicos/química , Volatilização
20.
Mater Sci Eng C Mater Biol Appl ; 81: 247-251, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28887970

RESUMO

We report the fabrication of novel nanofibers using naturally occurring antimicrobial honey incorporated in poly(1,4-cyclohexane dimethylene isosorbide trephthalate) (PICT) for the potential wound dressing applications. We fabricated PICT/honey using three blend ratios 90:10, 85:15 and 80:20 respectively. Morphology of PICT nanofibers and PICT/honey nanofibers was observed under Scanning Electron Microscope and it showed bead-free nanofibers. Fourier Transform Infrared Spectroscope was used to confirm the presence of honey in PICT electrospun nanofibers. Tensile strength of PICT/honey nanofibers was slightly reduced with variation in effect of elongation. Water contact angle measurements were done with the static contact angle by a contact angle meter, which showed that hydrophobicity was decreased by adding the honey. The XPS spectra showed that honey was present in the PICT/honey nanofibers. The release behavior of honey was investigated by UV-visible Spectrophotometer. The release was complete in 15min and the maximum release of honey was 72mg/L in 10min. Therefore, PICT/honey nanofibers having 15% concentration of honey are suitable for good elastic behavior and tensile strength as compared to other concentrations of honey.


Assuntos
Nanofibras , Cicloexanos , Cicloexilaminas , Mel , Isossorbida , Resistência à Tração
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